* {
	margin: 0;
	padding: 0;
	-webkit-box-sizing: border-box;
	-moz-box-sizing: border-box;
	box-sizing: border-box;
}

body {
	background: #f9f9f9;
	font-family: -apple-system, system-ui, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

ul {
	list-style-type: none;
}

a {
	color: #b63b4d;
	text-decoration: none;
}

/** =======================
 * 左侧菜单栏
 ===========================*/
 .accordion {
 	width: 100%;
 	max-width: 360px;
 	background: #FFF;
 	-webkit-border-radius: 4px;
 	-moz-border-radius: 4px;
 	border-radius: 4px;
 	overflow: auto;
 }

.accordion .link {
	cursor: pointer;
	display: block;
	padding: 15px 15px 15px 42px;
	color: #4D4D4D;
	font-size: 14px;
	font-weight: 700;
	border-bottom: 1px solid #CCC;
	position: relative;
	-webkit-transition: all 0.4s ease;
	-o-transition: all 0.4s ease;
	transition: all 0.4s ease;
}

.accordion li:last-child .link {
	border-bottom: 0;
}

.accordion li i {
	position: absolute;
	top: 16px;
	left: 12px;
	font-size: 18px;
	color: #595959;
	-webkit-transition: all 0.4s ease;
	-o-transition: all 0.4s ease;
	transition: all 0.4s ease;
}

.accordion li i.fa-chevron-down {
	right: 12px;
	left: auto;
	font-size: 16px;
}

.accordion li.open .link {
	color: #b63b4d;
}

.accordion li.open i {
	color: #b63b4d;
}
.accordion li.open i.fa-chevron-down {
	-webkit-transform: rotate(180deg);
	-ms-transform: rotate(180deg);
	-o-transform: rotate(180deg);
	transform: rotate(180deg);
}

.accordion li .first{
	background: #d6e9c6;
	font-size: 18px;
}

 .submenu {
 	display: none;
 	background: #EEE;
 	font-size: 14px;
 }

 .submenu li {
 	border-bottom: 1px solid #ddd;
 }
 
.submenu li i.fa-check {
	position: relative;
	right: auto;
	left: -10px;
	top: 0px;
	font-size: 16px;
}

 .submenu a {
 	display: block;
 	text-decoration: none;
 	color: black;
 	padding: 12px;
 	padding-left: 42px;
 	-webkit-transition: all 0.25s ease;
 	-o-transition: all 0.25s ease;
 	transition: all 0.25s ease;
 }

 .submenu a:hover {
 	background: #b63b4d;
 	color: #FFF;
 }
 
 .submenu .active a {
 	background: #444359;
 	color: #FFF;
 }

.learning-sidebar {
	position: fixed;
	top: 0;
	bottom: 0;
	z-index: 5;
	display: block;
	width: 300px;
	font-weight: 500;
	-webkit-backface-visibility: hidden;
	backface-visibility: hidden;
	-webkit-transition: 0.3s transform;
	transition: 0.3s transform;
	transform: translateX(0);
	-webkit-box-shadow: 0px 0px 5px rgba(0, 0, 0, 0.08);
	-moz-box-shadow: 0px 0px 5px rgba(0, 0, 0, 0.08);
	box-shadow: 0px 0px 5px rgba(0, 0, 0, 0.08);
	overflow: auto;
}

.learning-sidebar::-webkit-scrollbar {
  width: 4px;
}
.learning-sidebar::-webkit-scrollbar-thumb {
  background-color: #d9d9d9;
}

/*
右侧内容页
*/
.learning-main {
    position: absolute;
    height: 100%;
    width: 100%;
    padding-left: 320px;
    -webkit-transition: padding 0.3s;
    transition: padding 0.3s;
}

#iframe-content{
	height: 100%;
}

.chapter-main{
	margin-right: 20px;	
}

.chapter-main h1{
	padding-bottom: 9px;
    margin: 40px 0 20px;
    border-bottom: 1px solid #eee;
}

#video-main{
	display: none;
}

.chapter-content{
	margin: 20px 0 20px 0;
}

.chapter-video{
	margin-bottom: 20px;
}